Embodiments of the invention relate to circuit boards, socket mounts, and contact pins.
Burn-in is a semiconductor industry manufacturing process for screening out non-functional chips or devices. The chip may be inserted into a socket (commonly referred to as a burn-in socket), this socket holds the chip in place while providing electrical continuity from the chip to a printed circuit board (PCB).
Burn-in sockets are generally soldered to the printed circuit boards. The solder can be used to electrically and mechanically secure the socket to the printed circuit board. The burn-in socket (BIS) may include contact pins. The length of the contact pin that protrudes from the bottom of the socket into the PCB for soldering is called a solder-tail. When a socket is de-soldered from a PCB, solder remnants are left on the solder-tail. These solder remnants may reduce the reliability of the socket, and/or increase the diameter of the contact pin, making it difficult to reuse the socket.
In order to remove the socket, the solder may be reheated, which can damage the socket and reduce its reliability when reused. In addition, the reheating process may affect adjacent sockets. Further, soldering may cause thermal stress which may lead to plastic deformation. Finally, desoldering may cause solder bridging of solder remnants on the socket solder-tails.
FIG. 1 is a side view of an embodiment of the invention including a printed circuit board assembly with a mounted socket.
FIG. 2 is a side view of an embodiment of the invention including a printed circuit board assembly with an unmounted socket.
FIG. 3 is a side view of an embodiment of the invention including a printed circuit board assembly.
FIG. 4 is a top view of an embodiment of the invention.
FIG. 5 is a side view of a contact element according to an embodiment of the invention.
FIG. 6 is a cross-sectional side view of plating layers that may be included in an embodiment of the invention.
FIG. 7 is a top view of another embodiment of the invention.
FIG. 8 is a top view of another embodiment of the invention.
FIG. 9 is an exploded perspective view of an embodiment of the invention, including a contact element sheet and a circuit board.
FIG. 10 is a side view of a circuit board and contact element sheet, according to an embodiment of the invention.
FIG. 11 is a side view of a disassembled circuit board according to an embodiment of the invention.
FIG. 12 is a side view of an embodiment of the invention, including a circuit board assembly.
FIG. 13 is a side view of an embodiment of the invention, including a disassembled circuit board and contact elements.
FIGS. 14-17 are side views illustrating other embodiments of the invention.
FIG. 18 is a perspective view of another embodiment of the invention.